This invention relates to a chair type stair elevating device that permits ascending and descending of stairs while sitting on a chair, and more particularly a rack or chain structure as a driving means for moving a chair along a guide rail.
As a welfare device for handicapped people having difficulties in ascending and descending stairs, a chair type stair elevating device having a chair movable along guide rails provided along the stairs is provided so that it is possible to ascend and descend the stairs simply by sitting on the chair.
With a conventional chair type stair elevating device 1 shown in FIGS. 10 and 11, guide rails B are provided along the inclination of stairs A. The guide rails B comprise parallel rails 2 and 3. An elevating unit 4 is mounted on the rails 2, 3 through a plurality of guide rollers 12, 13. The elevating device 1 has a chair 9 comprising a seat 5, a footrest 6, a backrest 7 and armrests 8. By activating the elevating unit 4 by controlling a switch while seated on the chair 9, the chair moves along the rails 2, 3, so that it is possible to ascend and descend the stairs A.
As a drive system for such a chair type stair elevating device 1, a rack 10 or chain is provided parallel to the rails 2, 3, and a pinion 11 or sprocket of the driving machine provided in the elevating unit 4 is meshed with the rack 10 or chain, thereby moving the chair 9 along the rails 2, 3 by the rotation of the pinion 11 or sprocket.
Such a driving arrangement by the rack 10 and pinion 11, or chain and sprocket, is established as a driving element which can cope with both straight and curved stairs. With the arrangement of the rack 10 in a conventional chair type stair elevating device 1, as shown in FIG. 11, the rack 10 was fixed to the outer surface of the guide rail 2, which was a steel or stainless steel pipe. The arrangement utilizing a chain has a similar structure.
Chair type stair elevating devices are mostly set in homes. With the structure in which the rack 10 or chain is fixed to the outer surface of the rail 2, the entire rack 10 or chain is visible. This lowers the design value of the entire device. Also, since the rack 10 or chain is present at a position at which it can be touched by hands, the hands may touch the shaft edge of the rack or chain and be injured. Also, clothes may be soiled or get caught by the rack 10 or chain.
An object of this invention is to provide a chair type stair elevating device in which by providing a rack or a chain in a guide rail in a hidden state, the rack or chain cannot be seen from outside, so that the design value of the entire device improves, and it is also possible to prevent injury or soiling of clothes.